#include<stdio.h>
int max(int x, int y)
{
	int tmp;
	if (x > y)
		tmp = x;
	else
		tmp = y;
	return tmp;
}
int min(int x, int y)
{
	int tmp;
	if (x > y)
		tmp = x;
	else
		tmp = y;
	return tmp;
}
int add(int x, int y)
{
	return x + y;
}
int sub(int x, int y)
{
	return x - y;
}
int main()
{
	int(*p[5])(int, int) = { max,min,add,sub };
	int num;
	num = (*p[2])(10, 20);
	printf("mun=%d\n", num);
	return 0;
}